1. Field of the Invention
The present invention relates generally to the field of refuse handling apparatus. More particularly, this invention relates to refuse collection bodies of a type having a hopper for receiving refuse and a storage area for storing refuse from the hopper and compressing it to increase storage capacity. In a further and more specific aspect, the present invention concerns novel features for providing a lightweight, structurally rigid collection body comprising a loading assembly for dumping refuse into an elevated hopper; a reception area for refuse dumped into the hopper; a storage area for storage and compaction of refuse; a packer assembly for compression of the refuse within the storage area; a tailgate providing access to the storage area; a latching mechanism for the tailgate; and an actuation system comprised of hydraulic and electrical components for controlling the operation thereof.
2. Description of the Related Art
Modern municipal governments must provide for the collection, removal, and disposal of community refuse. This service, provided either by the municipal government or by contract, consists of requiring the residents to amass their refuse in storage containers for routine collection by refuse collection vehicles. The containers are either provided by the residents or, when standardization is necessary, by the organization providing the service. Residential refuse is generally amassed and stored in containers having a ten to thirty gallon capacity. On a regular basis the containers are placed by the residents for scheduled pick up by the collection service at a designated location, most commonly at the curbside and alley line.
To efficiently perform the collection operation, the service ordinarily uses mechanized and automated refuse collection vehicles supplemented by manual labor. A refuse collection vehicle generally consists of a refuse collection body mounted upon a standard truck chassis, the body having a reception area for the refuse and a storage area where the refuse is stored and generally compacted. The vehicle is attended by a crew of workers that attended to operation of the vehicle and perform loading chores of either manually conveying refuse from collection containers or operating automatic loading devices.
Commonly, the reception area includes a hopper into which refuse is dumped. The hopper may be positioned at a conveniently low loading height so that containers may be manually emptied by workers, or the hopper may be positioned higher on the refuse collection vehicle and accessed by a mechanical loading apparatus which lifts the container and dumps its contents into the hopper. Means are generally provided for transferring the refuse from the hopper to the storage area. The storage area is typically equipped with a packer assembly for compressing loose refuse into a smaller volume so that the carrying capacity of the vehicle is increased. The storage area also typically includes an unloading means for ejecting refuse from the storage area at the disposal site.
Considerable thought has been directed by many in the refuse collection industry towards the development of refuse collection technology. As a result, it is generally agreed that the most efficient method of collecting refuse is for the refuse to be provided at streetside locations in relatively large containers of uniform dimensions which are handled by automated equipment. The containers may, for example, be of sufficient size to service several households. The refuse collection vehicle is equipped with a self-loading device which lifts and dumps the container. Increased load carrying capacity of the vehicle is achieved through the use of compactor-type bodies which compress loose refuse into a smaller area within the storage area. The refuse collection industry has seen numerous designs for accomplishing one or more of these functions, each with its own advantages and disadvantages.
For example, it is well-recognized that a compactor-type body is desirable, but this is accomplished in various ways, usually with reciprocating platen or auger-type packer mechanisms. Loading is accomplished by front, side, or rear mounted mechanisms which may incorporate either fixed or extendible length arms. Refuse may be removed from the collection body either by expulsion by the compactor mechanism or by tilting the body to allow gravity to assist in dumping.
There are a number of particular problems which require better solutions. First, because prior art reciprocating packers are normally perform a packing operation in only one direction, termed the forward stroke, normally defined as being away from the vehicle cab towards the rear end by expansion of a piston, the return stroke constitutes wasted motion and wasted time. Furthermore, dumping of the refuse container into the collection body must be coordinated with the packing action to prevent the accumulation of refuse at the rearward or backside of the platen. While an auger arrangement provides continuous operation, it is at the expense of increased manufacturing costs and decreased reliability. Subjected to unequal forces and having bearings at only one end, the device can be wedged to a stop. In either case, the packing mechanism requires power from the vehicle engine for powering; the load placed on the engine by the packing actuating system precludes the simultaneous performance of the packing operation and transportation of the collection vehicle by the vehicle engine. It is desirable to perform multiple, simultaneous operations for speed and efficiency.
Second, with the increased size of the refuse collection containers, the collection bodies of most refuse collection vehicles have also grown to accommodate larger loads. However, these larger collection bodies have an increased tare weight due to the additional weight required by structural members required to accommodate the weight of the refuse and also by the force exerted against the collection body walls as the refuse is compacted. The walls of the present storage bodies are generally bulky and normally include vertical and/or horizontal bracing elements welded to the walls to rigidify and strengthen the walls or bulky support structures for bracing the storage body. Such walls and structures are expensive to construct, reduce the payload that the vehicle can carry, and diminish the general exterior appearance of the storage body. They further disturb the aerodynamic shape of the refuse collection vehicle which correspondingly decreases the gas mileage of the refuse collection vehicle during normal operation, thus increasing its operating cost. The increased forces necessary for compacting a larger, heavier load of refuse also cause a higher damage rate in the wall structure, necessitating routine replacement; if expensive advertising artwork has been applied to the outer wall, the artwork must be reapplied to a replaced outer wall, thus further increasing expense.
Third, to further enhance the automated collection of refuse, many collection bodies incorporate a tailgate assembly mounted to swing rearwardly and act as a closure for the rearward opening. These tailgate assemblies are normally bulky and incorporate complex mechanical features for latching and unlatching the tailgate assembly with the rearward opening. However, the accessible rearward opening allows refuse collected within the storage container to be ejected from the rearward opening. To this end, apparatus currently exist for either tilting the storage body upwardly to allow gravity to move the refuse from the storage area and outwardly through the rearward end for dumping, or direct ejection of the refuse outwardly through the rearward end. To eject the refuse outwardly through the rearward end of the storage body, innovators have adapted packing mechanisms which operate for not only transferring and packing refuse into the storage area from the reception area, but also for ejecting the refuse outwardly through the rearward end for deposit at suitable waste disposal sites. Although exemplary for intended use, these packing mechanisms are generally bulky, mechanically inefficient, and costly.
Fourth, packing mechanisms can have a number of moving parts involving linkages, rollers, gears, bearings and the like. When refuse of a random nature and high compaction forces are involved, the probability of damage or jamming of the mechanism is high. It would be desirable for a packing assembly to have a low number of moving parts.
Fifth, a collection body usually requires a significant amount of modification to the vehicle chassis in order to integrate the collection body with the vehicle chassis for operation. These modifications may consume significant amounts of manpower to effect or void warranties offered by the vehicle manufacturer. These modifications may also place significant burdens on the engine and drive train of the vehicle so that its performance is impaired; alternatively, they may dictate use of a vehicle which is larger and heavier than necessary or practical. It is desirable to provide a collection body requiring minimal or no modification to the vehicle, other than what is necessary to operationally connect and integrate its components with those of the vehicle.
Sixth, during normal operations, a number of refuse loads are dumped into the hopper before a packing operation is initiated. During movement of the vehicle between pickup locations, air turbulence and high air flow may cause the refuse contained in the hopper to blow out and thus litter the area. It would be desirable to provide a means of attenuating such air movement and prevent such loss of refuse material.
Seventh, it is common practice within the refuse collection technology to use mechanical sensing devices and relays in the sequencing and control of the various components of the collection body. it is thought that mechanical devices have sufficient structural strength to withstand the often harsh environment commonly experienced during ht erefuse collection process. For example, it is common practice to steam clean the interior and exterior of collection bodies to prevent corrosion and buildup of debris; linkages and sensors must be able to withstand these cleaning operations. However, mechanical devices are prone to wear and generally large and heavy. They also require more electrical current to operate. Newer solid state electronics offers devices which are light and inexpensive and require only a low-amperage signal. It would be desirable to replace such mechanical devices with modern, solid state devices for maintainability and weight reduction purposes.
It would be highly advantageous, therefore, to provide a collection body which would solve the foregoing problems in a satisfactory way.
Accordingly, what is needed is an improved refuse collection vehicle which provides the following features: higher payload to tare weight ratio than heretofore; stronger, lightweight sides which can withstand the high compaction forces; installation to a vehicle chassis without modification to the chassis; easy replacement of side walls without defacing or replacing expensive artwork on the exterior surfaces; operation of the compactor during a loading cycle or transportation mode; and improved resistance to refuse loss from wind force during transportation.
In light of the foregoing discussion, a general object of the present invention is to provide a refuse collection body having improved maintenance and weight characteristics over prior such devices.
Another object of the present invention is to provide a refuse collection body which can be configured to a selected chassis as a unit without major modification or reconfiguration of the vehicle.
Yet another object of the present invention is to provide a refuse collection body with its major operational components located above a lower plane of the collection body so that it can be placed on the upper surface of the chassis as a unit through use of a crane or other lifting arrangement and operationally attached to the chassis through a plurality of attachment means without disturbing the pre-existing vehicle chassis components.
Yet another object of the present invention is to provide a novel tailgate articulation and latching mechanism which prevents undue wear on the gasket between the tailgate and the rear end of the collection body.
Yet another object of the present invention is to provide a refuse collection body having improved, double-walled side structures which are sufficiently strong enough to withstand outwardly directed pressure resulting from packing operations normally occurring in standard refuse handling operations.
Yet another object of the present invention is to provide a refuse collection body with a storage area having an inner wall which can be easily replaced if damaged, without disturbing the outer wall of the storage area.
Yet another object of the present invention is to provide a self-supporting refuse collection body with a storage area having side walls constructed as an elongated, longitudinal beam which supports the collection body components on the vehicle chassis and withstands outwardly-directed buckling forces.
Yet another object of the present invention is to minimize the tendency of air turbulence and high air flow to blown refuse from hopper and reception area.
Yet another object of the present invention is to provide multi-panel cover which partially covers the packer piston, which extends over the vehicle cab when the packer is at rest position, and provides wind protection to the refuse reception area of the collection body to prevent refuse from being blown from the reception area by moving air.
Yet another object of the present invention is to provide a refuse collection body having a system of low amperage, infrared sensors used to control and direct the operation of the packer.
Yet another object of the present invention is to provide a refuse collection body having a hydraulic system which can operate the packer while the vehicle is in transit without overheating the hydraulic pump or hydraulic fluid or lugging down the engine.
Other objects and advantages of the present invention will be set forth in part in the description and in the drawings which follow and, in part, will be obvious from the description or may be learned by practice of the invention.
To achieve the foregoing objects, and in accordance with the purpose of the invention as broadly described herein, the present invention provides refuse collection vehicle consisting of a vehicle with a cab and a chassis and a collection body mounted on the chassis. The collection body is constructed as a unit with all components mounted thereon so that they do not interfere with mounting the collection body to a chassis. The collection body is attached to the chassis at a plurality of attachment points using standard means known to the industry such as bolts, welding, pins, and the like. In this manner, a new collection body may be easily installed on an old vehicle chassis when the collection body is worn out or an old collection body can be installed on a new vehicle chassis. The collection body is self supporting which allows it to be lifted by a crane or like apparatus at a plurality of lifting points without causing undue stress on the body. The hydraulic pump and hydraulic fluid reservoir are designed to be mounted under the vehicle chassis at a convenient position depending upon the particular chassis design.
The collection body is comprised of a reception area adjacent to the vehicle cab for receiving refuse and a storage area adjacent to the reception area for storage and compacting of refuse. Within the collection body is a packer assembly reciprocating from a first position in the proximity of the front wall of the collection body adjacent to the cab to a second position in the proximity of the rear of the collection body, so as to move refuse from the reception area to the storage area and to pack refuse within the storage area. A loader means is side mounted from points on the top side of the collection body for automated loading of refuse from containers placed alongside the road. The loading means may be any of a number of automated loading mechanisms known to the industry which are designed for lateral extension from the collection body from a top mounted guiding mechanism, acquiring loading refuse containers located alongside the vehicle, lifting them from a ground position to a position over the top of the collection body, and dumping the contents of the refuse container into the reception area of the collection body. A tailgate removably covers the rear end of the collection body.
The collection body is constructed as a storage area having a pair of side structures which are in concept self-supporting longitudinal beams. These side structures are constructed using a longitudinal a upper framing member, a lower triangular beam member, a planar inner wall, and a curved outer wall. This novel method of side structure construction permits the inner wall to be replaced when it is damaged during normal operation of the packer assembly within the collection body without interference with the outer curved wall. The outer wall can thus be adorned with expensive artwork for identification, advertisement, and routine damage to the inner wall will not necessitate replacement and redecoration of the outer wall. Further, the curved outer wall is smooth in aspect which promotes ease in steam cleaning and aerodynamic efficiency.
The tailgate is articulated by a novel hydraulic piston arrangement whereby the extension of the tailgate piston first unlatches the tailgate from locking engagement with the collection body and then swings the tailgate upwardly. This swinging movement eliminates any lateral movement of the tailgate along any axis of the collection body to prevent undue wear on any gasket material which may surround the rear opening of the collection body.
The electrical system features low amperage sensors which determine the position of the packer assembly to control its movement. A novel electrical circuit which is believed to be new to the refuse collection art uses ladder logic to sequence the movement of the packer assembly and prevent injury to maintenance personnel. The circuit employs retroflective infrared sensors which are more reliable than mechanical sensors and promote low maintenance cost for the collection body.
The hydraulic system consists of a unique design for directing hydraulic fluid to the packer piston to allow use of the packer while the vehicle is in operation or while other systems such as the loading means are in use. This design involves dividing the hydraulic fluid line supplying hydraulic fluid to the extension side of the packer piston so that it is delivered through a plurality of lower capacity solenoid operated valves instead of one high capacity hydraulic valve. Each of the smaller valves is of a size suitable for less robust hydraulic operation, e.g the tailgate operation or operation of the loading means; but when operated in parallel such as described in the invention, they permit a high flow rate of hydraulic fluid to the packer piston without the associated heat being generated, which in turn results in lower cost components and longer maintenance cycles. This design permits the use of a lower capacity hydraulic pump which can operate at higher revolutions per minute without overheating.
The present invention will now be described with reference to the following drawings, in which like reference numbers denote the same element throughout.